Author Topic: Head Raising Mechanisms - descriptions (Read 5316 times)

slowzuki · « **on:** September 30, 2004, 07:03:44 PM »

Trying to finish off the mill and the garage door spring 'taint gonna cut it to lift the electric motor! I've got some ideas to work with I'm gonna list, lets hear yours!

-power (acme) screws
pros-
simple to motorize, balance and install, self locking
cons-
time to order, cost

-hydraulic cylinder (turner mill style)
pros-
simple to power, powerful, accurate/infinite positioning, self locking
cons-
would add 3 ft to height of my mill, cost

-cable winder gearing added the garage door spring
pros-
garage door stuft is there already, easier to motorize
cons-
Worried about torque on set screws on garage door cable drums, non-self locking

-Chain walker like WM
pros-
Proven design, easy to motorize, self locking
Cons-
Cost, parts aren't available in town

-Chainfall hung over top, pull chain run through exhaust tubing and rewelded so it is in better location.
Pros-
have chainfall, self locking
Cons -
difficult to power and route pull chain, balancing

I'm leaning powerscrew but could be swaying. Comments? Additions? Anything?

Furby · « **Reply #1 on:** September 30, 2004, 07:21:31 PM »

What's the weight of the saw head?

slowzuki · « **Reply #2 on:** September 30, 2004, 07:24:21 PM »

Well, some math here, 200+80+40+80 about 400 lbs give or take I'm guessing?

Quote

What's the weight of the saw head?

Furby · « **Reply #3 on:** September 30, 2004, 07:54:51 PM »

Can ya do some kind of counter balance along with the overhead door spring? How about two springs, one for each side of the head.

I think someone on the forum is useing a 12 volt winch for up and down. Just get power in/power out.

Let me look at my mill.

slowzuki · « **Reply #4 on:** September 30, 2004, 08:10:57 PM »

Well, the overhead door spring is sort of a counter balance. It is taking about 125 lbs load right now. I can't fit another due to space. I can get a heavier spring to take 225 lbs or so of load but still not enough and I have no locking.

I have a 12 volt winch but the mill is 220V so no dice. I could run a worm gear cable winch to provide some pull and self locking like the little wood buddy does.

Ken

Quote

Can ya do some kind of counter balance along with the overhead door spring? How about two springs, one for each side of the head.

I think someone on the forum is useing a 12 volt winch for up and down. Just get power in/power out.

Let me look at my mill.

Wudman · « **Reply #5 on:** September 30, 2004, 08:27:47 PM »

Slowzuki,

I'm using Acme threaded rod (1" x 5 threads per inch). I built a four post head and have a rod on either side connected by chain and sprocket. I welded a 3/4 inch bolt to the top of one rod and use a Milwaukee reversible drill to raise and lower over large distances. I attached an old steering wheel to the other side for fine adjustments by hand. The system works very well for me. I'm using a 5 HP electric motor so I'm a little lighter than your setup, but the Acme rod should handle anything you throw at it.

I am gathering parts to add some hydraulics to the mill, and when I do I'll probably use a hydraulic motor to turn the Acme rod. By the way, I haven't had any problems with sawdust messing up the system.

Wudman

Furby · « **Reply #6 on:** September 30, 2004, 08:36:11 PM »

I was kinda thinking an actual weight and cable run through several pulleys. "Could" make it small, but still might be in the way.

Heck, that overhead door spring isn't taking much, is it? :-/

slowzuki · « **Reply #7 on:** September 30, 2004, 08:49:48 PM »

I've run out of room to add more pulleys unfortunately and the spring drums are about out of room to store wire... Actual garage doors use 2 springs and they only weigh 200 lbs or so.
Ken

Quote

I was kinda thinking an actual weight and cable run through several pulleys. "Could" make it small, but still might be in the way.

Heck, that overhead door spring isn't taking much, is it? :-/

slowzuki · « **Reply #8 on:** September 30, 2004, 08:51:36 PM »

Wudman, what do you use for thrust bearings at the bottom or top? And what do you use for engaging the head to the screw? Just a nut or more to it?
Thanks!
Ken

Quote

Slowzuki,

I'm using Acme threaded rod (1" x 5 threads per inch). I built a four post head and have a rod on either side connected by chain and sprocket. I welded a 3/4 inch bolt to the top of one rod and use a Milwaukee reversible drill to raise and lower over large distances. I attached an old steering wheel to the other side for fine adjustments by hand. The system works very well for me. I'm using a 5 HP electric motor so I'm a little lighter than your setup, but the Acme rod should handle anything you throw at it.

I am gathering parts to add some hydraulics to the mill, and when I do I'll probably use a hydraulic motor to turn the Acme rod. By the way, I haven't had any problems with sawdust messing up the system.

Wudman

Wudman · « **Reply #9 on:** September 30, 2004, 09:14:24 PM »

Ken,

I used flange bearings at the top of the rods, so the head is basically hanging from those bearings. At the bottom, I just welded an acme nut to the head. It's a simple system and very solid.

Wudman

slowzuki · « **Reply #10 on:** September 30, 2004, 10:25:33 PM »

Whats a flange bearing

Got a pic?

ex-racer · « **Reply #11 on:** October 01, 2004, 05:46:06 AM »

Regarding the cost of Acme powerscrews and the followers (nuts) for them, I got some from old hospital beds.
The ones I got were 1 inch diameter, and moved exactly 1/4 inch per turn, which was perfect for a manual (crank handle) operation.

Flange bearing pic below.

Ed

redpowerd · « **Reply #12 on:** October 01, 2004, 06:01:04 AM »

im a little confused on your design from these posts, but it sounds a bit like the Kasco design. mine uses threaded rod attached to the carrage, with a threaded sprocket (one on each corner)linked with a chain to a reversable dc motor. the rod is attached to the carrage with
a pin, so fine tuning the rig to the carrage is as easy as removing the pin and twisting the rod up or down. im sure larry_copas wouldnt mind snapping some photos for ya, he may allready have some!

slowzuki · « **Reply #13 on:** October 01, 2004, 06:09:31 AM »

Ok, thats what I pictured for a flange bearing, I've got them on my garage door spring setup. Wouldn't have guessed it could take that much thrust load. Do you use a split collar to keep it from pulling out?

So where does one find old hospital beds eh

Quote

Regarding the cost of Acme powerscrews and the followers (nuts) for them, I got some from old hospital beds.
The ones I got were 1 inch diameter, and moved exactly 1/4 inch per turn, which was perfect for a manual (crank handle) operation.

Flange bearing pic below.

Bruce_A · « **Reply #14 on:** October 01, 2004, 06:10:07 AM »

Trailer tongue jacks might be an option. Replace handles with sprockets and chaindrive.

Wudman · « **Reply #15 on:** October 01, 2004, 06:29:05 AM »

Bearing thrust loads was/is something that I was/am a bit concerned with. I'm not sure what they can stand, but I'm not turning them at any speed so bearing failure shouldn't be any problem. With that said, I made sure nothing could fall if a bearing failed catastrophically. The flange bearings are sitting on top of their supports, with a hole drilled through the support being just a tad larger than the 1" rod. I tack welded the bearing stop collar to the Acme rod, because I knew I was loading the whole deal with some thrust forces that It wasn't really designed to take. Even if I have a catastrophic bearing failure, the stop collars would prevent anything from falling.

Wudman

redpowerd · « **Reply #16 on:** October 01, 2004, 06:36:03 AM »

wudman, your lifting mech isnt attached to the rig but to the carrage?
the kasco uses stationary rods, i take it yours move. lemme look see if i have some of larrys pics.

Wudman · « **Reply #17 on:** October 01, 2004, 06:45:46 AM »

Red,

That would be correct. My Acme rod turns. At the top they are suspended in the flange bearings. At the bottom, an Acme nut is welded to the saw carriage and the rods thread through them. Turn the rods and the head will travel up or down. Right now I am using a Milwaukee variable speed drill to power up or down. It works pretty good for me. When I make it to a more permanent location, I'll probably put a hydraulic motor on it.

Wudman

GF · « **Reply #18 on:** October 01, 2004, 08:02:46 AM »

I used acme rods on mine the head itself along with the 30HP 4 cyclinder weights about 1500lbs. I dont think I would weld the nuts, I would build a "u" shape bracket to go around the nuts that keep it from spinning and then bolt that to the frame. Should the nut ever need to be replaced just unbolt the u bracket and unthread the nut. This also will allow you to fine tune each side or corner individually by loosening the u bracket and turning the nut to the next flat area. Thats how the one is I built. I use a hydraulic motor to power mine up and down.

GF · « **Reply #19 on:** October 01, 2004, 08:08:57 AM »

Also if you run the threaded rod throguh any type square tubing make sure to make the hole oversize or put a bushing through the tube, otherwise your acme threaded rod could catch the edge and strip a thread, i used high tensile strength steel rods on mine they are 1" X 6' and cost around $48 each.

Forestry ForumSponsored by:

Author Topic: Head Raising Mechanisms - descriptions (Read 5316 times)

Forestry Forum
Sponsored by: